Nouska

One should not get too hung up on the state of the polar vortex at this stage - it is expected to develop by late october. If you had been looking at the appended charts in the daily NWP output, in context of the OPI, all hope would be seen to be gone. For this year, so many of the things now considered important, were in the wrong phase ie. wQBO, peak of solar max and transitional ENSO. It is important to remember that nothing is ever as it seems in weather or the modelling of it. The month in entirety http://www.meteociel.fr/modeles/archives/archives.php?mode=2&month=10&day=1&year=1978&map=4&hour=0 Culminating in this apparently impenetrable object!

Hi Sean, the Jamstec is no better - no worse - than any other long range model. Here is a screen shot of the forecast from September 2013 :- It was very wrong! - though, it had a lot of company in that respect. http://www.jamstec.go.jp/frcgc/research/d1/iod/e/seasonal/outlook.html

Whilst the highlighted is very true, Nick, the European map is appended with a geopotential height anomaly scale to correspond with positive or negative score. A southerly tracking jet stream is indicated - diffluent blocking perhaps? Of course, the whole of the W. European coast could have a large negative GPH, as it did last winter. I would prefer to see other countries shaded as well.

They have certainly been omitting some of the less favourable runs in the past two weeks - it is a moot point as the final figure is based on the reanalysis of the whole month - at least, I hope it is.

There are several papers discussing lack of ice in the Barents, Kara and Laptev as being contributors to cold winter weather at lower latitudes - the side by side certainly highlights the infill of ice in that area during autumn 2013. Laptev is ice free this year, a strong advance of the SAI and a negative trending OPI - a good test for several new areas of research.

Au contraire! When Riccardo posted this on the seventh of November, I bet the jaws were hitting the desks and there was a sudden run on 'Depends!

When I was looking at the graph in the EPF research paper I posted in the Stratosphere thread, it immediately caught my eye that there was a correlation with the misfit parts of the OPI graph in the early decades. As solar max progresses, the fit gets better - pattern established by then whereas transition is more difficult to call? No match in the super Nino years of 97/98 though. There was the double whammy of solar max and high energetic particle count on two out of three occasions - with what we now know about solar effects I wouldn't rule it out as a contributor to the discrepancy.

In last years forecast Riccardo has annotated the October composite and made some comments about how he arrived at the result. It refers to some of the points being raised here. The chart - The discussion -

Yes, John - this is the subject of a recent post by Michael Ventrice. The charts in the article will help show what you are talking about. How this effects us downstream will depend on the amplification of the wave pattern. http://www.wsi.com/blog/energy/introducing-a-new-atmospheric-el-nino-southern-oscillation-index-its-current-state-and-upcoming-winter-implications/

My interpretation may be way off, but as I currently understand the ideal is to have wave 2 activity to split the polar vortex. To this end it is important to have the two ridges opposite one another - from Pacific to Atlantic. The very low analogue years have that cross polar strip of positive heights - Aleutians to Scandinavia - I suspect Greenland to Kamchatka would fit the bill as well. In some recent runs, that has been observed, in others the angle is offset to some degree.

Thank you, Ed - a very comprehensive 'mode d'emploi' in your opener. http://journal.frontiersin.org/Journal/10.3389/fphy.2014.00025/full?utm_source=newsletter&utm_medium=web&utm_campaign=Physics-w18-2014 This article was published in the spring of this year so don't know if it has been discussed in other topics - didn't see it in the previous thread. It is looking at another aspect of solar influence on the winter polar stratosphere, namely energetic particle forcing. Some have posited that sudden bursts of solar activity have scuppered forecasts - could this research offer validation of the idea?

Another red warning for the SE of France. http://vigilance.meteofrance.com/ The map of projected rainfall totals from Keraunos looks pretty horrific. At last update, September and first trimester of October was running at over 300% - what on earth will the tally be by the time this month is out?

Is this index based on something along the lines of the Polar/Eurasia index with particular focus on the October reading? http://www.cpc.ncep.noaa.gov/data/teledoc/poleur.shtml

Quite striking water vapour imagery with this system. Image source: IMO SEVIRI index. http://brunnur.vedur.is/myndir/seviri/

You should also add 1956 to your list of biggest differential. What stands out is that these summer/autumn change over ambiguities all followed a very cold winter. This year has a very small figure of difference - that seems to be just as likely to follow a mild winter - as has been the case this year. What might be the artefact of a cold winter that would impact August more than September?

The swallows that breed in our barn and local steadings all seem to have left some time in late August. I wonder if it was the period of very cool nights that affected their food source or do they move on the basis of prevailing weather, irrespective of insect supply? The other migratory birds were away early too.

I posted this link in the snow and ice thread yesterday - hadn't seen this thread previously. https://forum.netweather.tv/topic/81111-snow-and-ice-in-the-northern-hemisphere-autumnwinter-2014/?p=3031924

I have no doubt that factory fishing of the primary food source is having a huge impact on the ability to provide sufficient food for the chicks but it does not provide an answer as to why so many eggs are failing to hatch. That would imply something impacting the birds and having an effect on their fertility or maybe something that would cause genetic defects in the growth of the embryo chick. It is a while since I lived in the NE of Scotland and regularly walked the Moray beaches but even way back then, the number of dead sea birds washed ashore seemed to be growing year on year.

I was reprimanded for posting scientific articles up-thread but I think it is important to look at the drivers of the patterns that will bring the snow. Some of us have a deeper interest than just a green map with a splodge of white on it - would be better if the images were saved - the majority of posts just update to the most recent image. http://nldr.library.ucar.edu/repository/assets/osgc/OSGC-000-000-019-877.pdf Using NCEP–NCAR reanalysis and Japanese 25-yr Reanalysis (JRA-25) winter daily (1 December– 28 February) data for the period 1979–2012, this paper reveals the leading pattern of winter daily 850-hPa wind variability over northern Eurasia from a dynamic perspective. The results show that the leading pattern accounts for 18% of the total anomalous kinetic energy and consists of two subpatterns: the dipole and the tripole wind patterns. The dipole wind pattern does not exhibit any apparent trend. The tripole wind pattern, however, has displayed significant trends since the late 1980s. The negative phase of the tripole wind pattern corresponds to an anomalous anticyclone over northern Eurasia during winter, as well as two anomalous cyclones occurring over southern Europe and in the mid- to high latitudes of East Asia. These anomalous cyclones in turn lead to enhanced winter precipitation in these two regions, as well as negative surface temperature anomalies over the mid- to high latitudes of Asia. The intensity of the tripole wind pattern and the frequency of its extreme negative phase are significantly correlated with autumn Arctic sea ice anomalies. Simulation experiments further demonstrate that the winter atmospheric response to Arctic sea ice decrease is dynamically consistent with the observed trend in the tripole wind pattern over the past 24 winters, which is one of the causes of the observed declining winter surface air temperature trend over Central and East Asia. The results of this study also imply that East Asia may experience more frequent and/or intense winter extreme weather events in association with the loss of Arctic sea ice.

This area is well known for dust plumes - a combination of geological and meteorological processes at work. Page 13 in this document pictures very similar to what we have seen on camera. I would wonder if there is now an added component of heat from the ground causing additional thermal rising. http://landbunadur.is/landbunadur/wglbhi.nsf/Attachment/Olafur%20Arnalds%202010%20IAS/$file/Olafur%20Arnalds%202010%20IAS.pdf

Some recent research articles on the things that may influence our winter weather patterns. I don't see a solar/weather/climate thread so will pop it in here. http://www.issibern.ch/teams/interplanetarydisturb/wp-content/uploads/2014/04/Mursula_03_2014.pdf http://www.atmos-chem-phys.net/13/6275/2013/acp-13-6275-2013.pdf

Indeed it is, got it on Firefox - a combination of an old IE not loading properly and an old duffer using it. Subtle differences in the synoptics between the papers; suppose it depends on which records/reports are used.

I was just looking back through my records for the last time we failed to reach 20c on an August day - 2010. A scan of the archives located this chart - not a million miles away from what is forecast next week. That was quite a nice memory recall in December of that year. http://www.meteociel.fr/modeles/archives/archives.php?mode=0&month=8&day=24&year=2010&map=0&hour=12

Thanks Knocker. That one is not available to read but one I have in my files gives a very detailed account of the consequences along with some reanalysis of the weather patterns. http://www.clim-past.net/9/1161/2013/cp-9-1161-2013.pdf

WWOSC conference starts tomorrow. Book of abstracts. http://asp-us.secure-zone.net/v2/index.jsp?id=144/235/1368&lng=en